I also play the button accordion and I have a video "Fastest button accordionist" at :
http://recordsetter.com/world-record/button-accordionist/14401#contentsection
If you like, watch another "crazy" playing by a Russian button accordionist at:
http://www.youtube.com/watch?v=5FuK6noEi18
He plays 28 buttons/second - not a clear and distinct sound...but anyway, it' fun...